Immediately after Election Day, Russia began a "spear-phishing" campaign to try to trick people into revealing their email passwords, targeting U.S. government employees and think tanks that specialize in national security, defense and foreign policy, the report released on Friday said.
"This campaign could provide material for future influence efforts as well as foreign intelligence collection on the incoming administration's goals and plans," the report said.
That could prove awkward for President-elect Donald Trump. The president-elect wants to warm relations with Russia and has repeatedly denounced the intelligence community's assessment that the Kremlin interfered in the election. The new report goes even further by explicitly tying Russian President Vladimir Putin to the meddling and saying Russia had a "clear preference" for Trump in his race against Hillary Clinton.
The report, which called Russia's meddling the "boldest effort yet" to influence a U.S. election, was the most detailed public account to date of Russian efforts to hack the email accounts of the Democratic National Committee and individual Democrats, among them Clinton's campaign chairman, John Podesta.
It said that Russian government provided emails to WikiLeaks even though the website's founder, Julian Assange, has repeatedly denied that it got the emails it released from the Russian government. The report noted that the emails could have been passed through middlemen.
"We assess with high confidence that the GRU (a top Russian intelligence agency) relayed material it acquired from the DNC and senior Democratic officials to WikiLeaks," the report said.
Russia also used state-funded propaganda and paid "trolls" to make nasty comments on social media services, the report said. Moreover, intelligence officials believe that Moscow will apply lessons learned from its activities in the election to put its thumbprint on future elections in the United States and allied nations.
The public report was minus classified details that intelligence officials shared with President Barack Obama on Thursday.
At 8 a.m. Friday, Director of National Intelligence James Clapper, CIA Director John Brennan, National Security Agency director Adm. Mike Rogers and FBI Director Jim Comey trekked to Capitol Hill to share the classified version with eight top congressional leaders. Soon after, some of those same intelligence officials traveled to New York to brief the president-elect at Trump Tower.
In a brief interview with The Associated Press, Trump said he "learned a lot" from his discussions with intelligence officials, but he declined to say whether he accepted their assertion that Russia had intruded in the election on his behalf.
"It was a really great meeting, I really like those people a lot," said Trump, who has been in a standoff with U.S. intelligence agencies since winning the election. "I learned a lot and I think they did also."
Just hours before he was briefed, Trump dismissed the assessment and told The New York Times the focus on Russia's involvement is a "political witch hunt" by his adversaries. "They got beaten very badly in the election," he said. "They are very embarrassed about it. To some extent, it's a witch hunt. They just focus on this."
After finally seeing the intelligence behind the claims of the outgoing Obama administration, Trump released a one-page statement that did not address whether Russia sought to meddle. Instead, he said, "there was absolutely no effect on the outcome of the election" and that there "was no tampering whatsoever with voting machines."
Intelligence officials have never made that claim. And the report stated that the Department of Homeland Security did not think that the systems that were targeted or compromised by Russian actors were "involved in vote tallying."
The report lacked details about how the U.S. learned what it said it knows, such as any intercepted conversations or electronic messages among Russian leaders, including Putin, or about specific hacker techniques or digital tools the U.S. may have traced back to Russia in its investigations. Exactly how the U.S. monitors its adversaries in cyberspace is a closely guarded secret, since revealing such details could help foreign governments further obscure their activities.
The unclassified version included footnotes acknowledging that it "does not include the full supporting information on key elements of the influence campaign." It said its conclusions were identical to the classified version, which was more detailed.
The unclassified report said the Russian effort was both political and personal.
"Russia's goals were to undermine public faith in the U.S. democratic process, denigrate Secretary Clinton and harm her electability and potential presidency," it said. "We further assess Putin and the Russian government developed a clear preference for President-elect Trump."
Putin most likely wanted to discredit Clinton because he blames her for inciting mass protests against his regime in late 2011 and early 2012, and because he resents her for disparaging comments she has made about him, the report said.
Before the intelligence agencies completed their assessment, Obama announced sanctions against Russia. Trump has not said whether he will undo them once he takes office, but lawmakers are calling for more punitive measures against Russia and have little to no appetite to roll back any current sanctions.
Trump said he would appoint a team within three months of taking office to develop a plan to "aggressively combat and stop cyberattacks." Also Friday, many lawmakers renewed their demand for the creation of a special bipartisan panel to investigate.
Associated Press writers Eric Tucker, Chad Day and Jack Gillum contributed to this report.
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